Study of Variable Scroll Type Turbocharger (Performance Test in Diesel Engine)

This report describes with the performance test of a diesel engine using a new variable scroll type turbocharger (VS turbocharger).

The experimental variable scroll is relatively a simple structure in which several scroll pieces are jointed by pins, located inside of exhaust turbine inlet flow passage. The scroll is varied by the control rod according to exhaust flow volume, and as a result, the A/R ratio that effects to the performance of turbocharger is varied.

To compare the performances of variable scroll type turbocharger with a conventional turbocharger with waste gate, a test of diesel engine equipped with each was performed. The experimental results show that VS turbocharger increases more than the conventional turbocharger in boost pressure at lower engine speed, and the wide torque range is ensured. Also, the experimental scroll pieces did not showed signs of trouble from heat wear during experimentation ensuring reliability.